County, King, 20050309, Channel Migration Areas in King County: King County, King County, WA.
This is a Vector data set. It contains the following vector data types (SDTS terminology):
The map projection used is NAD 1983 HARN StatePlane Washington North FIPS 4601 Feet.
Planar coordinates are encoded using coordinate pair
Abscissae (x-coordinates) are specified to the nearest 0.00025
Ordinates (y-coordinates) are specified to the nearest 0.00025
Planar coordinates are specified in foot_us
The horizontal datum used is D North American 1983 HARN.
The ellipsoid used is GRS 1980.
The semi-major axis of the ellipsoid used is 6378137.0.
The flattening of the ellipsoid used is 1/298.257222101.
Sequential unique whole numbers that are automatically generated.
|MODERATE||The moderate hazard area is located between the outer boundary of severe hazard and the maximum probable limits of future migration.|
|POTENTIAL||The area is not yet a channel migration zone, but could become one.|
|SEVERE||The severe hazard area includes the width of the river channel itself plus a width equal to one hundred (100) years times the average annual channel migration rate. It is assumed that channel will migrate for fifty (50) years on both sides of the present channel location during this hundred year period.|
Coordinates defining the features.
Area values generated by software.
Perimeter values generated by software.
See also Ken Zweig, DNRP/WLRD - Floodplain and River Management Program, 206-477-4732 for more details.
This dataset can be use to estimate the channel migration for seven rivers: White River, Raging River, Tolt River, Three Forks area of Snoqualmie River, Cedar River, Green River, and the South Fork of the Skykomish River.
Perkins, S.J, 19930101, Green River Channel Migration Study.
Perkins, S.J, 19960101, Channel Migration in the Three Forks Area of the Snoqualmie River.
The amended channel migration public rule became effective July 13, 2018
The amended channel migration public rule became effective December 25, 2019.
CMZ boundaries typically have positional accuracy of 0-30 feet, in some areas with few control points such as eastern King County the positional accuracy could be as much as 50-100 feet. The data should not be reproduced or used at a scale larger than 1:2400.
This dataset covers only the following areas of King County: middle White River, Raging River, Tolt River, South Fork Skykomish River, Three Forks area of Snoqualmie River, Cedar River, and Green River.
This dataset meets standard coverage QA/QC checks such as labelerrors, nodeerrors.
Are there legal restrictions on access or use of the data?
- Access_Constraints: None
- King County data are made available with the understanding that they shall be used exclusively by the obtainer or his/her authorized agents. Digital products may not be reproduced or redistributed in any form or by any means without the express written authorization of King County.
King County disclaims any warranty of use of any digital product or data beyond that for which it was designed.
|Data format:||ESRI Shapefile|
Contact KCGIS Client Services for the cost of reproduction - <http://www.kingcounty.gov/operations/GIS/ClientServices.aspx>